1pc D40 Achromatic Objective Lens for DIY Refractive Astronomical Telescope - 40mm D, 205mm Focal Length(48F981 Green Film AR0862)

D40 achromatic objective lens devised for self-made refractive astronomical telescopes, enhancing your stargazing experience. Features a 40mm actual diameter and 205mm focal length, providing clear and sharp images of objects. Coated with adhesive blue film for improved light transmission and reduced chromatic aberration, ensuring vibrant colors and details. Easy to assemble with clear instructions; simply orient the thin side of the lens towards the scene for optimal performance. Compatible with various telescope models, making it a versatile addition to your astronomy toolkit for both beginners and enthusiasts.